﻿/* Copyright (c) 2010 EPiServer AB
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
 * of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
 * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
 * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using EPiServer.Web;
using System.Web;
using EPiServer.Configuration;

namespace EPiServer.CdnSupport
{
    /// <summary>
    /// Static file handler that implements "far future" expires for requests that are coming via the CDN
    /// </summary>
    public class CdnStaticFileHandler : StaticFileHandler
    {
        protected override void SetCachePolicy(HttpContext context, DateTime fileChangedDate)
        {
            if (!CdnModule.IsRequestComingFromCdn(context))
            {
                base.SetCachePolicy(context, fileChangedDate);
                return;
            }

            // Future dates are not allowed and will cause a exception in SetLastModified
            if (fileChangedDate > DateTime.UtcNow)
                fileChangedDate = DateTime.UtcNow;
            context.Response.Cache.SetLastModified(fileChangedDate);           
            context.Response.Cache.SetCacheability(HttpCacheability.Public);
            context.Response.Cache.SetExpires(DateTime.UtcNow.AddYears(1));
            context.Response.Cache.SetValidUntilExpires(true);
            context.Response.Cache.VaryByParams.IgnoreParams = true;
            context.Response.Cache.SetOmitVaryStar(true);
            context.Response.Cache.SetNoServerCaching();
        } 
    }
}
